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New Member

inspect esmtp

Pix 525 with Failover UR bundle IOS 8.0.2

Microsoft Exchange Server

I'm receiving complaints from a very small group of people that we are not receiving they're emails, sometimes up to 4 days.

I was told that "inspect esmtp" should be disabled and may solve the problem.

I would like to hear from anyone that can enlighten me on this subject.

Keith Beaul

Network Administator

Mental Health Centre

New Member

Re: inspect esmtp


Had ran into a similar issue in the past. Cisco is pretty strict about following the actual RFC's in regards to esmtp functionality. As opposed to me typing everything out, check out the link below and go to "ESMTP Overview". That gives a pretty solid explanation.

New Member

Re: inspect esmtp

Hi Michael;

Thank you for the link. I downloaded and printed the PDF version.

If you don't mind me asking, how did you resolve the issue? Did you turn off "inspect esmtp"?

Not sure I want to do that because I did read on Cisco that it also helps prevent certain types of hacking.

Another thought I have is this. Could certain attachments within the email cause this problem aswell.

Thanks again and I look forward to hearing from you.

Happy holiday.


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